Enterprises in the data storage industry perpetually face demand from their customers to produce storage solutions that achieve ever-increasing data storage density. One approach to achieving high storage density is to pack as many disk drives as possible into a disk array enclosure. Ideally, each disk drive can be carrier-less, thereby minimizing the enclosure area occupied by any given disk drive.
This approach, however, is fraught with difficulties. For example, spacing between disk drives installed in neighboring chassis bays is often too small to permit personnel, limited to use of their fingertips, to establish a firm grasp of an individual disk drive. Thus, such personnel can have difficulties removing a disk drive from a chassis, not being able to apply sufficient extracting force to overcome the resistance of mated connectors between the disk drive and an enclosure midplane. Inserting a disk drive into the midplane can also become an imprecise art; personnel may not insert the disk drive sufficiently far to make adequate electrical contact. In addition, some disk drives require a companion “personality card” that determines the functionality of the disk drive. A difficulty posed by a carrier-less disk drive is how to package the personality card with the disk drive so that both may be installed together in a chassis bay.
Using a carrier for the disk drive can mitigate some of these difficulties, albeit with tradeoffs. Disk drives with carriers generally occupy more enclosure area than carrier-less disk drives do. The use of carriers thus runs contrary to efforts to increase storage density. Further, carriers may introduce complexity and expense to the constructing disk drive assemblies, often involving several small, hard-to-handle hardware components, such as screws and rivets.